Key value cache systems, for example Memcached, have become quite popular, in part because of the fast growth of Web 2.0 web sites. Many large web sites, such as youtube.com, facebook.com, twitter.com, and wikipedia.com, are built using key value cache systems. Because the performance of relational databases cannot support the scalability of those large web sites, Memcached is used to cache the hot data and thus avoid database access for most data queries. Key value cache systems currently do not support temporal features for data. Youtube is a registered trademark of Google Incorporated in the United States and/or other countries. Facebook is a registered trademark of Facebook Incorporated in the United States and/or other countries. Twitter is a registered trademark of Twitter Incorporated in the United States and/or other countries.